Abstract：
OBJECTIVE: To measure the trunk vertical displacement (VD) in horses trotting on a water treadmill (WT) at different water depths (WDs) and speeds.
METHODS: 6 sound Standardbred horses (median age 12 years [IQR:10.5-12]).
METHODS: The horses were trotted on a WT at 2 speeds (3.5 m/s and 5 m/s) and during 4 conditions: dry treadmill (DT), WD at mid-cannon (WD-CAN), mid-radius (WD-RAD), and shoulder (WD-SHOUL). The dorsoventral movement was obtained with accelerometers placed over the withers, thoracolumbar junction (T18), tuber sacrale (TS), and sacrum (S5). The VD was defined with the median value of the upward (Up) and downward (Down) amplitudes of the vertical excursion during each stride. The difference of VD at each sensor location was compared between the DT and the 3 WDs, and between the 2 trotting speeds for the same condition.
RESULTS: The VD amplitudes were significantly increased at any sensor location when trotting in water at WD-CAN and WD-RAD compared to DT (P < .05 for all), with the highest increase at WD-RAD and T18. When the speed increased from 3.5 to 5 m/s, the VD amplitudes were significantly decreased at T18 at each water level (P = .03), and at WD-RAD only for the withers and TS (P = .03).
CONCLUSIONS: Both water depth and speed affect the trunk VD in horses at trot on a WT with an opposite effect. The VD increases when increasing the WD up to mid-radius, while the VD decreases when increasing the trotting speed, with the main effects observed at the thoracolumbar junction.
METHODS: 6 sound Standardbred horses (median age 12 years [IQR:10.5-12]).
METHODS: The horses were trotted on a WT at 2 speeds (3.5 m/s and 5 m/s) and during 4 conditions: dry treadmill (DT), WD at mid-cannon (WD-CAN), mid-radius (WD-RAD), and shoulder (WD-SHOUL). The dorsoventral movement was obtained with accelerometers placed over the withers, thoracolumbar junction (T18), tuber sacrale (TS), and sacrum (S5). The VD was defined with the median value of the upward (Up) and downward (Down) amplitudes of the vertical excursion during each stride. The difference of VD at each sensor location was compared between the DT and the 3 WDs, and between the 2 trotting speeds for the same condition.
RESULTS: The VD amplitudes were significantly increased at any sensor location when trotting in water at WD-CAN and WD-RAD compared to DT (P < .05 for all), with the highest increase at WD-RAD and T18. When the speed increased from 3.5 to 5 m/s, the VD amplitudes were significantly decreased at T18 at each water level (P = .03), and at WD-RAD only for the withers and TS (P = .03).
CONCLUSIONS: Both water depth and speed affect the trunk VD in horses at trot on a WT with an opposite effect. The VD increases when increasing the WD up to mid-radius, while the VD decreases when increasing the trotting speed, with the main effects observed at the thoracolumbar junction.
摘要：
目的：测量在不同水深（WDs）和速度下在水上跑步机（WT）上小跑的马的躯干垂直位移（VD）。
方法：6匹声音标准马（中位年龄12岁[IQR：10.5-12]）。
方法：将马在WT上以2种速度（3.5m/s和5m/s）和4种条件小跑：干跑步机（DT），中炮（WD-CAN）的WD，中半径(WD-RAD),和肩膀（WD-SHOUL）。背腹运动是用放在肩带上的加速度计获得的，胸腰椎交界处(T18),块茎骶骨（TS），和骶骨（S5）。VD定义为每个跨步期间垂直偏移的向上（向上）和向下（向下）幅度的中值。比较了DT和3个WDs之间每个传感器位置的VD差异，并且在相同条件下的2个小跑速度之间。
结果：与DT相比，WD-CAN和WD-RAD在水中小跑时，任何传感器位置的VD振幅均显着增加（全部P<0.05），WD-RAD和T18的增幅最高。当速度从3.5米/秒增加到5米/秒时，在每个水位的T18处，VD振幅显着降低（P=.03），在WD-RAD下仅适用于枯萎和TS(P=0.03)。
结论：水深和速度都会影响WT上小跑时马匹的躯干VD，效果相反。当WD增加到中间半径时，VD增加，而当增加小跑速度时，VD降低，在胸腰椎交界处观察到的主要效果。
方法：6匹声音标准马（中位年龄12岁[IQR：10.5-12]）。
方法：将马在WT上以2种速度（3.5m/s和5m/s）和4种条件小跑：干跑步机（DT），中炮（WD-CAN）的WD，中半径(WD-RAD),和肩膀（WD-SHOUL）。背腹运动是用放在肩带上的加速度计获得的，胸腰椎交界处(T18),块茎骶骨（TS），和骶骨（S5）。VD定义为每个跨步期间垂直偏移的向上（向上）和向下（向下）幅度的中值。比较了DT和3个WDs之间每个传感器位置的VD差异，并且在相同条件下的2个小跑速度之间。
结果：与DT相比，WD-CAN和WD-RAD在水中小跑时，任何传感器位置的VD振幅均显着增加（全部P<0.05），WD-RAD和T18的增幅最高。当速度从3.5米/秒增加到5米/秒时，在每个水位的T18处，VD振幅显着降低（P=.03），在WD-RAD下仅适用于枯萎和TS(P=0.03)。
结论：水深和速度都会影响WT上小跑时马匹的躯干VD，效果相反。当WD增加到中间半径时，VD增加，而当增加小跑速度时，VD降低，在胸腰椎交界处观察到的主要效果。
